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<h4 class="subsection" id="Else-1"><span>4.2.4 Else<a class="copiable-link" href="#Else-1"> &para;</a></span></h4>

<a class="index-entry-id" id="index-_0023else"></a>
<p>The &lsquo;<samp class="samp">#else</samp>&rsquo; directive can be added to a conditional to provide
alternative text to be used if the condition fails.  This is what it
looks like:
</p>
<div class="example smallexample">
<div class="group"><pre class="example-preformatted">#if <var class="var">expression</var>
<var class="var">text-if-true</var>
#else /* Not <var class="var">expression</var> */
<var class="var">text-if-false</var>
#endif /* Not <var class="var">expression</var> */
</pre></div></div>

<p>If <var class="var">expression</var> is nonzero, the <var class="var">text-if-true</var> is included and
the <var class="var">text-if-false</var> is skipped.  If <var class="var">expression</var> is zero, the
opposite happens.
</p>
<p>You can use &lsquo;<samp class="samp">#else</samp>&rsquo; with &lsquo;<samp class="samp">#ifdef</samp>&rsquo; and &lsquo;<samp class="samp">#ifndef</samp>&rsquo;, too.
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